Thin layer chromatography coating device

ABSTRACT

Coating device for applying thin layers of uniform and defined thickness of adsorption agent onto chromatography plates comprising two vertical side members, two connecting parts affixed thereto, the connecting parts being mounted at an angle to each other to form a trough with a slit at the bottom thereof to permit slow flow-through of coating material, the height difference between the lower edges of the connecting parts and side members, respectively, defining the thickness of the coating applied.

United States Patent Jaworek [54] THIN LAYER CHROMATOGRAPHY 3,124,826 3/1964 1V1idd1ebrooks........118/415 X COATING DEVICE 1,957,611 5/1934 Pelton....................118/415 X i 3,381,661 5/1968 Brandel.................l18/415 X [72] f 8132 3,140,504 7/1964 Knops ....401/193 Tutzmo, upper Bavaria, Gen'nany Primary Examiner-John P. McIntosh Attorney-Burgess, Dinklage & Sprung Assignee: Boehringer Mannheim Gmbl-l,

Mannheim 7 ABSTRACT Coating device for applying thin layers of uniform and [22] Filed: April 20, 1970 [21] Appl. No.: 29,930

defined thickness of adsorption agent onto chromatog- [30] Foreign Application Priority Data raphy plates comprising two vertical side members,

two connecting parts affixed thereto, the connecting May 2, 1969 Germany..........P 19 22 528.6

parts being mounted at anjangle to each other to form a trough with a slit at the bottom thereof to permit [52] US. Slow flow through of coating material the'height [51] Int. 5/02 ference between the lower edges of the connecting [58] Field 01 Search 18/415, 413; 401/193 parts and side members, respectively, defining the thickness of the coating applied.

3 Claims, 4 Drawing Figures 5 6] References Cited UNITED STATES PATENTS 3,209,389 10/1965 Stahl......................118/415X PATENTED nEc 2 6 I972 SHEET 1 BF 2 PAIENTED DH: 2 6 I972 SHEET 2 OF 2 THIN LAYER CHROMATOGRAPHY COATING DEVICE The present invention is concerned with a coating device for use in thin layer chromatography which permits the application of thin layers of a suspension of adsorption agent of uniform and defined thickness onto chromatography plates.

Coating devices for this purpose are already known. Thus, in German Pat. specification No. 1,129,730, there is described a device which comprises a flat base plate and a coating means, the latter containing a collar for the reception of the coating mass, this collar being rotatably mounted in the square block, and the collar and the block each have a slit for the outflow of coating mass, the block outlet slit being of variable height.

Furthermore, from German Pat. specification No.

1,963,989, there is known a coating device which comprises a base plate and tiltable chamber which can be moved back and forward thereon, the chamber having an adjustable outlet slit through which the suspension can emerge upon tilting the chamber.

In addition, from German Utility Model No. 1,867,651, there is known a coating device which comprises a bar provided with slots or recesses with which the adsorption agent suspension can be smoothly coated onto a substrate plate.

Finally, a coating device is known which comprises a substrate plate and a slider movable thereon, the slider having two vertically arranged side parts and two connecting parts which are also arranged vertically forming a trough with the surface of the plate to be coated. By adjustment of the height of the connecting parts, a slit of differing breadth can be produced between the surface of the plate and the connecting part, through which slit the suspension in the trough can flow out.

The known coating devices are of relatively expensive and complicated construction and suffer from several disadvantages. The thickness adjustability necessitates the use of a precision device which is expensive to produce. Thin layer chromatography has now been standarized to certain layer thicknesses but it is either not possible to produce layers of precise thickness or possible only at considerable expense. Due to the weight of these known devices, the edges of the glass plates used as substrates can easily be damaged and then cannot be used again for the desired purpose. In particular, plate substrates are also disadvantageous because there can only be used glass plates with precise critical dimensions. Furthermore, the plates often become jammed so that further coating is interrupted. None of these devices, apart from the abovementioned bar, can be moved back and forth without the already coated layer being scratched off again. Swollen gels can only be applied with these devices with difficulty. The bar-shaped device is not a coating device in the strict sense of the word since it does not have a supply container for the slurry to be applied and only a single plate can be coated after calculation of the necessary amount of slurry.

Therefore, there is a need for a coating device which is of simple construction and is also cheap to produce and which does not suffer from the above-mentioned disadvantages but which, nevertheless, permits the production of layers of precise thickness.

According to the present invention, there is provided a coating device which fulfills these requirements.

Thus, according to the present invention, there is provided a coating device for thin layer chromatography plates, which comprises two vertically arranged side parts and at least two connection parts, each of the side parts having a guide strip on the lower edge thereof, the connecting parts being arranged non-adjustably and at an angle to one another so as to form a slit therebetweemthe breadth of which slit permits a slow flowthrough of material to be applied and the lower edges of the connecting parts are constructed as coating edges, the difference in height between the lower edges of the connecting parts and the lower edges of the side parts determining the thickness of the layer to be applied to a substrate or plate.

The side parts and the connecting parts comprising the new device according to the present invention are preferably made of a synthetic resin which, desirably, is transparent.

In operation, the coating device according to the present invention is placed on a layer carrier plate, the breadth of which corresponds to the distance between the guide strips on the lower edges of the side parts. The material to be coated on is placed in the trough formed by the connecting parts, whereupon the device is moved over the carrier plate. The device can be moved back and forth so that any material which emerges too quickly can be uniformly smoothed out by again moving the device across it. In the case of the use of swellable material, the layer thickness can be regulated again at any time. The mass to be applied is readily accessible from above and, if required, can be thickened or thinned during the coating operation.

The production of the device is extremely simple. The previously produced component parts are merely connected to one another, whereupon, for example, the precise layer thickness is determined by grinding down the lower edges of the connecting parts.

For a better understanding of the present invention, reference will now be made to the accompanying drawings, in which:

FIG. 1 is a perspective view of one embodiment of the coating device according to the present invention;

FIG. 2 is a section along the line IllI of FIG. 1;

FIG. 3 shows another embodiment of the coating device according to the present invention with which two different layer thicknesses can be applied; and

FIG. 4 is a section along the line IV-IV of FIG. 3.

The coating device shown in FIG. 1, which can be made, for example, of transparent synthetic resin, has two vertical side parts I and la. The lower edges 2 and 2a of the side parts are each provided with a guide strip 3. The side parts 1 and la are joined together by two connecting parts 4 and 5. The connecting parts are arranged at an'angle to one another, as can be readily seen from FIG. 2. At their lower ends, the connecting parts form a longitudinal slot 7, the breadth of which is so dimensioned that the material to be coated on cannot flow therethrough too quickly. The connecting parts 4 and 5 have lower edges 8 and 9, the difference in height of which to the lower edges 2 and 2a of the side parts 1 and la, respectively, determines the thickness of the coated-on layer.

The device is placed in a carrier plate to be coated, the breadth of which plate corresponds precisely to the distance between the inner sides 6 of the guide strips 3.

The device thereby rests on the carrier plate with the lower edges 2 and 2a of the side parts 1 and 1a. After placing the coating material into the trough formed by the connecting parts 4 and 5, as well as the side parts 1 and 1a, the material flows through the slit 7 and is smoothly applied to the carrier plate by moving the device back and forth, a layer thus being formed, the thickness of which corresponds to the distance between the carrier plate surface and the lower edges 8 and 9 of the connecting parts 4 and 5. This distance is the same as the difference in height between the lower edges 2 or 2a of the side parts and the lower edges 8 and 9 of the connecting parts.

FIGS. 3 and 4 show an embodiment of the device according to the present invention with three connecting parts 4, and 10. The two outer connecting parts 4 and 10 are arranged substantially vertically, whereas the connecting part 5 lying therebetween is at an angle of about 40-50 to the vertical. The three connecting parts 4, 5 and 10 together form slits 7 and l l. The side parts 1 and 1a have, apart from the guide strips 3 on the lower edges 2 and 2a, corresponding guide strips 12 on the parallel, opposite upper edges 13 and 13a. Lower edges 8 and 9 of the connecting parts 4 and 5 are at a definite distance from the lower edges 2 and 2a of the side parts and upper edges 14 and 15 of the connecting parts 5 and 10 are also at a definite but different distance from the upper edges 13 and 13a of the side parts. Edges l6 and 17 of the outer connecting parts 4 and 10 lying opposite the slots have a distance from the side edges 2 and 2a or 13 and 13a, respectively, which is greater than the distance of the corresponding connecting part edges 8 and 9 or 14 and 15 to the side part edges 2 and 2a or 13 and 13a, respectively. In this way, by simply turning over the coating device, another layer thickness can be obtained without the advantages of the device being impaired.

What is claimed is:

l. Coating device for thin layer chromatography comprising two substantially vertically disposed rigidly mounted side parts and two vertical connecting parts affixed thereto, and a third connecting part arranged therebetween at an angle of 4050 to the vertical, said third connecting part forming an outlet slit with each of the two said vertical connecting parts, the breadth of which said slits permitting a slow flowthrough of coating material, guide strips being provided on each upper and lower edge of the side parts, and the lower edges of all connecting parts being constructed as coating edges, the difierence in height between the lower edges of the connecting parts and the lower edges of the side parts determining the thickness of the coating to be applied to a substrate or plate.

2. Coating device according to claim 1 wherein the side parts and connecting parts are made of a synthetic resin.

3. Coating device according to claim 2 wherein the synthetic resin is transparent.

. CE QKH ECATE 0F COHRECLKON 39mm? mm Decemb'gr 25,1972

ifatcnt No.

Dieter Jaworek Invcntoflsfi It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrccted as shown below:

under "Inventor",

For 4 "Tutzino u er Bavaria" I i v v I Read 7 Tutzing 9 Upper Bavaria Signedand se al d this 10th day of Jilly 1973 (SEAL) W A Attesc:

"EDWARDMELETCHER R. V "Rene Tegtmeyer 'A't'testing Officer I Acting Commissioner of Patents R 9040500049) I uscorlm-oc eoan pee 

1. Coating device for thin layer chromatography comprising two substantially vertically disposed rigidly mounted side parts and two vertical connecting parts affixed thereto, and a third connecting part arranged therebetween at an angle of 40*-50* to the vertical, said third connecting part forming an outlet slit with each of the two said vertical connecting parts, the breadth of which said slits permitting a slow flowthrough of coating material, guide strips being provided on each upper and lower edge of the side parts, and the lower edges of all connecting parts being constructed as coating edges, the difference in height between the lower edges of the connecting parts and the lower edges of the side parts determining the thickness of the coating to be applied to a substrate or plate.
 2. Coating device according to claim 1 wherein the side parts and connecting parts are made of a synthetic resin.
 3. Coating device according to claim 2 wherein the synthetic resin is transparent. 